/*
    This file is part of the substandard lisp implementation of Standard Lisp
    Copyright (C) 2011 Nicky Nickell

    substandard lisp is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

function std_gensym(a, env) {
  var gsnum = env.variables.get('*GSNUM');
  var gensym = new lisp_id('G' + gsnum.prin1());
  env.variables.set('*GSNUM', new lisp_integer(gsnum.value.add(1)));

  return gensym;
}

/*---
name: gensym
arity: 0
rest: false
ftype: FTYPE_EXPR

doc: |
  explaining what gensym is / how it is used!

tests: |
  (gensym) -> G1
  (gensym) -> G2
  (gensym) -> G3
  (gensym) -> G4
...*/
